Email messaging has become one of the most popular communications tools in industrialized society. The proliferation of personal computers for domestic and business use, coupled with the widespread use of the Internet as a global communications network, have resulted in email messaging being one of the most convenient forms of communication, in many instances more convenient than the telephone. Email messaging allows for the transmission of the written word in a form that is private and virtually instantaneous, and with the ability to attach documents is essentially unlimited in terms of the possible content and format of the message.
Email messaging also allows for the simultaneous transmission of messages to multiple senders. For this feature alone email messaging has become a very desirable marketing medium. All that is required is a mailing list or “group’ of email addresses, and the same promotional message can simultaneously be sent to a virtually unlimited number of recipients. Where a recipient has not previously indicated any interest in receiving messages from the sender, this practice is known as “spamming”, or Unsolicited Commercial E-mail (UCE.) Most Internet Service Providers (ISPs) prohibit spamming, which is considered undesirable and, to many recipients, irritating and wasteful of their time. Because spamming has become so popular, with the large number of purely promotional email messages received by many recipients (especially business recipients) it can be very time consuming for a recipient to regularly sort through their email messages to separate those that are wanted or necessary from those that are merely promotional and should be discarded.
Various types of solutions have been proposed and implemented to try to reduce spamming. Software is available that conceals an Internet user's email address, so that the owners of web sites visited by the user cannot determine the visitor's email address and therefore cannot add the user to a mailing list. This solution has limited utility, however, because as soon as the email address has been willingly provided by the user to a third party (for example with a request for information, goods or services), it can very quickly be disseminated for inclusion in email address lists maintained many other entities. As in the case of postal addresses, this type of demographic information is highly marketable. Moreover, an email address can often be fairly easily determined by other means, particularly in the case of a business where having a visible presence and being readily accessible is important to the success of the email user's business.
Email messaging programs often provide filters which allow a user to block or redirect received messages having, or missing, certain user-defined characteristics. However, this solution also has limited utility, because the recipient either has to have already received a message from the sender in order to block further messages from that sender (and there are also ways that a sender can hide or fake their identity to defeat such a blocking filter); or the recipient risks blocking messages that are actually useful or desirable, thereby generating “false positives.” In the case of a business in particular, it is often not practical for the recipient to ignore email messages just because they originate from unknown senders, as these can be a source of new business or an unknown party related to an existing business transaction or situation.
However, in many instances it is also not practical for a recipient to qualify or verify every email sender that tries to send the recipient a message, as this can become even more time consuming than the existing practice of vetting and discarding unwanted email messages.